feat: consume new scope analysis package (#2039)

.cspell.json

@@ -77,6 +77,8 @@
     "Premade",
     "prettier's",
     "recurse",
+    "redeclaration",
+    "redeclarations",
     "redeclared",
     "reimplement",
     "resync",

.eslintrc.js

@@ -214,6 +214,7 @@ module.exports = {
         'packages/eslint-plugin-internal/tests/rules/**/*.test.ts',
         'packages/eslint-plugin-tslint/tests/rules/**/*.test.ts',
         'packages/eslint-plugin/tests/rules/**/*.test.ts',
+        'packages/eslint-plugin/tests/eslint-rules/**/*.test.ts',
       ],
       rules: {
         '@typescript-eslint/internal/plugin-test-formatting': 'error',

packages/eslint-plugin/docs/rules/no-redeclare.md

@@ -0,0 +1,69 @@
+# Disallow variable redeclaration (`no-redeclare`)
+
+## Rule Details
+
+This rule extends the base [`eslint/no-redeclare`](https://eslint.org/docs/rules/no-redeclare) rule.
+It adds support for TypeScript function overloads, and declaration merging.
+
+## How to use
+
+```jsonc
+{
+  // note you must disable the base rule as it can report incorrect errors
+  "no-redeclare": "off",
+  "@typescript-eslint/no-redeclare": ["error"]
+}
+```
+
+## Options
+
+See [`eslint/no-redeclare` options](https://eslint.org/docs/rules/no-redeclare#options).
+This rule adds the following options:
+
+```ts
+interface Options extends BaseNoShadowOptions {
+  ignoreDeclarationMerge?: boolean;
+}
+
+const defaultOptions: Options = {
+  ...baseNoShadowDefaultOptions,
+  ignoreDeclarationMerge: true,
+};
+```
+
+### `ignoreDeclarationMerge`
+
+When set to `true`, the rule will ignore declaration merges between the following sets:
+
+- interface + interface
+- namespace + namespace
+- class + interface
+- class + namespace
+- class + interface + namespace
+- function + namespace
+
+Examples of **correct** code with `{ ignoreDeclarationMerge: true }`:
+
+```ts
+interface A {
+  prop1: 1;
+}
+interface A {
+  prop2: 2;
+}
+
+namespace Foo {
+  export const a = 1;
+}
+namespace Foo {
+  export const b = 2;
+}
+
+class Bar {}
+namespace Bar {}
+
+function Baz() {}
+namespace Baz {}
+```
+
+<sup>Taken with ❤️ [from ESLint core](https://github.com/eslint/eslint/blob/master/docs/rules/no-redeclare.md)</sup>

packages/eslint-plugin/docs/rules/no-shadow.md

@@ -0,0 +1,50 @@
+# Disallow variable declarations from shadowing variables declared in the outer scope (`no-shadow`)
+
+## Rule Details
+
+This rule extends the base [`eslint/no-shadow`](https://eslint.org/docs/rules/no-shadow) rule.
+It adds support for TypeScript's `this` parameters, and adds options for TypeScript features.
+
+## How to use
+
+```jsonc
+{
+  // note you must disable the base rule as it can report incorrect errors
+  "no-shadow": "off",
+  "@typescript-eslint/no-shadow": ["error"]
+}
+```
+
+## Options
+
+See [`eslint/no-shadow` options](https://eslint.org/docs/rules/no-shadow#options).
+This rule adds the following options:
+
+```ts
+interface Options extends BaseNoShadowOptions {
+  ignoreTypeValueShadow?: boolean;
+}
+
+const defaultOptions: Options = {
+  ...baseNoShadowDefaultOptions,
+  ignoreTypeValueShadow: true,
+};
+```
+
+### `ignoreTypeValueShadow`
+
+When set to `true`, the rule will ignore when you name a type and a variable with the same name.
+
+Examples of **correct** code with `{ ignoreTypeValueShadow: true }`:
+
+```ts
+type Foo = number;
+const Foo = 1;
+
+interface Bar {
+  prop: number;
+}
+const Bar = 'test';
+```
+
+<sup>Taken with ❤️ [from ESLint core](https://github.com/eslint/eslint/blob/master/docs/rules/no-shadow.md)</sup>

packages/eslint-plugin/docs/rules/no-unused-vars.md

@@ -1,7 +1,5 @@
 # Disallow unused variables (`no-unused-vars`)
 
-## PLEASE READ THIS ISSUE BEFORE USING THIS RULE [#1856](https://github.com/typescript-eslint/typescript-eslint/issues/1856)
-
 ## Rule Details
 
 This rule extends the base [`eslint/no-unused-vars`](https://eslint.org/docs/rules/no-unused-vars) rule.

packages/eslint-plugin/docs/rules/no-use-before-define.md

@@ -23,42 +23,34 @@ See [`eslint/no-use-before-define` options](https://eslint.org/docs/rules/no-use
 This rule adds the following options:
 
 ```ts
-interface Options extends BaseNoMagicNumbersOptions {
+interface Options extends BaseNoUseBeforeDefineOptions {
   enums?: boolean;
   typedefs?: boolean;
+  ignoreTypeReferences?: boolean;
 }
 
 const defaultOptions: Options = {
-  ...baseNoMagicNumbersDefaultOptions,
+  ...baseNoUseBeforeDefineDefaultOptions,
   enums: true,
   typedefs: true,
+  ignoreTypeReferences: true,
 };
 ```
 
 ### `enums`
 
-The flag which shows whether or not this rule checks enum declarations of upper scopes.
 If this is `true`, this rule warns every reference to a enum before the enum declaration.
-Otherwise, ignores those references.
+If this is `false`, this rule will ignore references to enums, when the reference is in a child scope.
 
-Examples of **incorrect** code for the `{ "enums": true }` option:
+Examples of **incorrect** code for the `{ "enums": false }` option:
 
 ```ts
-/*eslint no-use-before-define: ["error", { "enums": true }]*/
+/*eslint no-use-before-define: ["error", { "enums": false }]*/
 
-function foo() {
-  return Foo.FOO;
-}
-
-class Test {
-  foo() {
-    return Foo.FOO;
-  }
-}
+const x = Foo.FOO;
 
 enum Foo {
   FOO,
-  BAR,
 }
 ```
 
@@ -78,10 +70,8 @@ enum Foo {
 
 ### `typedefs`
 
-The flag which shows whether or not this rule checks type declarations.
 If this is `true`, this rule warns every reference to a type before the type declaration.
-Otherwise, ignores those references.
-Type declarations are hoisted, so it's safe.
+If this is `false`, this rule will ignore references to types.
 
 Examples of **correct** code for the `{ "typedefs": false }` option:
 
@@ -92,4 +82,25 @@ let myVar: StringOrNumber;
 type StringOrNumber = string | number;
 ```
 
-Copied from [the original ESLint rule docs](https://github.com/eslint/eslint/blob/a113cd3/docs/rules/no-use-before-define.md)
+### `ignoreTypeReferences`
+
+If this is `true`, this rule ignores all type references, such as in type annotations and assertions.
+If this is `false`, this will will check all type references.
+
+Examples of **correct** code for the `{ "ignoreTypeReferences": true }` option:
+
+```ts
+/*eslint no-use-before-define: ["error", { "ignoreTypeReferences": true }]*/
+
+let var1: StringOrNumber;
+type StringOrNumber = string | number;
+
+let var2: Enum;
+enum Enum {}
+```
+
+### Other Options
+
+See [`eslint/no-use-before-define` options](https://eslint.org/docs/rules/no-use-before-define#options).
+
+<sup>Taken with ❤️ [from ESLint core](https://github.com/eslint/eslint/blob/master/docs/rules/no-use-before-define.md)</sup>

packages/eslint-plugin/package.json

@@ -43,6 +43,7 @@
   },
   "dependencies": {
     "@typescript-eslint/experimental-utils": "3.10.1",
+    "@typescript-eslint/scope-manager": "3.10.1",
     "debug": "^4.1.1",
     "functional-red-black-tree": "^1.0.1",
     "regexpp": "^3.0.0",

packages/eslint-plugin/src/configs/all.ts

@@ -74,7 +74,11 @@ export = {
     '@typescript-eslint/no-non-null-asserted-optional-chain': 'error',
     '@typescript-eslint/no-non-null-assertion': 'error',
     '@typescript-eslint/no-parameter-properties': 'error',
+    'no-redeclare': 'off',
+    '@typescript-eslint/no-redeclare': 'error',
     '@typescript-eslint/no-require-imports': 'error',
+    'no-shadow': 'off',
+    '@typescript-eslint/no-shadow': 'error',
     '@typescript-eslint/no-this-alias': 'error',
     '@typescript-eslint/no-throw-literal': 'error',
     '@typescript-eslint/no-type-alias': 'error',
@@ -91,7 +95,6 @@ export = {
     '@typescript-eslint/no-unused-expressions': 'error',
     'no-unused-vars': 'off',
     '@typescript-eslint/no-unused-vars': 'error',
-    '@typescript-eslint/no-unused-vars-experimental': 'error',
     'no-use-before-define': 'off',
     '@typescript-eslint/no-use-before-define': 'error',
     'no-useless-constructor': 'off',

packages/eslint-plugin/src/rules/index.ts

@@ -51,7 +51,9 @@ import noNamespace from './no-namespace';
 import noNonNullAssertedOptionalChain from './no-non-null-asserted-optional-chain';
 import noNonNullAssertion from './no-non-null-assertion';
 import noParameterProperties from './no-parameter-properties';
+import noRedeclare from './no-redeclare';
 import noRequireImports from './no-require-imports';
+import noShadow from './no-shadow';
 import noThisAlias from './no-this-alias';
 import noThrowLiteral from './no-throw-literal';
 import noTypeAlias from './no-type-alias';
@@ -152,7 +154,9 @@ export default {
   'no-non-null-asserted-optional-chain': noNonNullAssertedOptionalChain,
   'no-non-null-assertion': noNonNullAssertion,
   'no-parameter-properties': noParameterProperties,
+  'no-redeclare': noRedeclare,
   'no-require-imports': noRequireImports,
+  'no-shadow': noShadow,
   'no-this-alias': noThisAlias,
   'no-throw-literal': noThrowLiteral,
   'no-type-alias': noTypeAlias,

packages/eslint-plugin/src/rules/no-empty-interface.ts

@@ -1,8 +1,5 @@
 import * as util from '../util';
-import {
-  AST_NODE_TYPES,
-  TSESLint,
-} from '@typescript-eslint/experimental-utils';
+import { TSESLint } from '@typescript-eslint/experimental-utils';
 
 type Options = [
   {
@@ -81,12 +78,7 @@ export default util.createRule<Options, MessageIds>({
             let useAutoFix = true;
             if (util.isDefinitionFile(filename)) {
               const scope = context.getScope();
-              if (
-                scope.block.parent &&
-                scope.block.parent.type ===
-                  AST_NODE_TYPES.TSModuleDeclaration &&
-                scope.block.parent.declare
-              ) {
+              if (scope.type === 'tsModule' && scope.block.declare) {
                 useAutoFix = false;
               }
             }